[CQ-Contest] Band Edge

dj7ww at t-online.de dj7ww at t-online.de
Sat Nov 14 09:28:21 EST 2020

The band edges in Germany with those bands are 7200, 3800 and 14350 kHz, in
SSB that is the carrier frequency.

To be on the safe side that means 14347kHz is the highest VFO frequency to
be used in SSB.


-----Original Message-----
From: CQ-Contest
[mailto:cq-contest-bounces+dj7ww=t-online.de at contesting.com] On Behalf Of
Edward Sawyer
Sent: Samstag, 14. November 2020 12:53
To: cq-contest at contesting.com
Subject: [CQ-Contest] Band Edge

Since the topic of Band Edge has come up.  I am interested in what people
think the band edge is on SSB.

I believe the FCC provides some guidance in Part 97.  They define the width
of an SSB signal I believe as 36dB down from the signal on the center
frequency.  This allows a "clear signal" to be closer to the band edge and
still be sufficient.  Rather than a "broad brush answer" of 3khz away.  In
fact, 3khz away isn't far enough if you are splattering 10 - 15khz wide with
signal energy above -36db.

I am assuming that most countries don't define the band edge other than
center frequency given that you always hear Europe on frequencies like
7199.9, 3799.9 and 14349.9.

I personally use 0.5khz above on USB and 2.8khz below.  I periodically get
the "you are out of band" quips from the khz cops that think 3.0 is written
in Part 97 somewhere.  Its not.  -36db is.  And 3khz comes from a "rounded
up" answer to how far away do you need to be to insure that the properly
modulated SSB signal is -36db down form the center frequency.

Ed  N1UR
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